000
FXUS63 KABR 082325 AAA
AFDABR
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
525 PM CST Thu Dec 8 2016
.UPDATE...
Issued at 523 PM CST Thu Dec 8 2016
See updated aviation discussion below.
&&
.SHORT TERM...(This Evening through Friday Afternoon)
Issued at 258 PM CST Thu Dec 8 2016
Some strings of lake effect clouds and possible light snow showers
remains off of Lake Oahe. The main impact at PIR has been BKN-OVC
sky cover at 1.3kft.
The Arctic sfcridge over the western half of the of South Dakota
this afternoon will slowly edge across our entire forecast area by
09Z Friday. The high will still be over ND through. The initial
weather change will continue to be the diminishing cloud cover this
afternoon, and weakening pressure gradient. After nearly 3 days, the
gusts over 25kts have finally ended. PW values overnight will fall
to 0.08 to 0.12 inches, before rebounding slightly southwest of PIR.
The main concerns for a well below normal temperatures close to the
MEX guidance (with -10F at ABR) will be the nearing mid to high
clouds currently over WY, and the fact at least at ABR that below
normal temperatures with little to no snow on the ground is a rare
event. Low level moisture just below 900mb also increases overnight
through the mid morning hours Friday. Went with temps overnight
ranging from the single digits above 0 over our MN counties, to the -
10 to -15 range across north central MN. With winds in our coldest
areas generally less than 5mph and only a few pixels getting to the -
25F criteria, will not issue a Wind Chill Advisory for the area. the
best chance would be over northern Corson County from 05Z-15Z
Friday.
Otherwise, the main story for this period will be light snow over
central SD on Friday, with totals generally around half an inch or
less. Expect highs in the single digits above zero northwest, up to
around 15 degrees elsewhere. This will be still around 15 degrees
below normal for this time of year.
.LONG TERM...(Friday Evening through Thursday)
Issued at 258 PM CST Thu Dec 8 2016
Fairly flat and fast flow is expected to continue across the region
for much of the period. The wave expected to bring snow to the area
on Saturday has now trended down in intensity somewhat, although mid
level frontogenesis progs still indicate some potential for a
banded snow event somewhere in the region. Exactly where this might
set up is still somewhat up in the air, but there has been a slight
shift south of the low/mid level baroclinic zone in the CMC/GFS such
that they look more like the ECMWF. The ECMWF is the lightest as far
as QPF is concerned. Another stronger wave moves mostly south of the
region on Sunday into Sunday night. Most of the measurable pcpn
from this system should be south of the ABR CWA. Other weak waves
are forecast during the period, but not much pcpn is expected until
perhaps late next week as the pattern begins to buckle. Both the
GFS/ECMWF start to dig a western conustrof at that time. As for
temperatures, they should remain below normal through the period
with a couple scheduled arctic outbreaks during the period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 523 PM CST Thu Dec 8 2016
With the exception of some lake effect MVFR cigs around the KPIR
area and some MVFR cigs across the far northeastern CWA this
evening, VFR conditions will prevail across the area tonight and
through the day Friday.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
SHORT TERM...KF
LONG TERM...TDK
AVIATION...Parkin